Diaphragm pump



NOV. 27, 1951 I R, VON ROTZ 2,576,200

DIAPHRAGM PUMP Filed May 6, 1949 B 2 V J ATTORNEY Patentecil Nov. 27,1,951l

DIAPIRAGMPUMP Robert Von Rotz, MManhasset, N. Y., assigner to .TheDayton Pump =& `Manufacturing Company,

Dayton, Oho,a corporatiomof AOhio @exitation-Mays, 1949;-seria11N0."91mm`9 claims. (Chios-315e) 1 This Ainvention relatest-o diaphragmpumps,particularly `as used in `water systemsand thelike for the transfer ofliquid from one place 'o'f storage to another.

Pumps fof `theclass-described `are characterized ley `a pumpingchamberwith-*which-Jcheck valve controlled" inlet and outletpassagesrcommunicate, there being ka diaphragm in the `pumping lchamber`which i`s"`flexe`d 'inranapproximately reciprocablemotion to 'inducefluid -fl-ow between 'the inlet and "'outlet'passa'ges Athroughlthepumping'chamber. Efforts'to improve such pump-are 'usually directedtto the supporting vand "guiding vmeans for the "diaphragm"`and =to theLactuating means therefor, 'with "the objects 'of "avoiding twisting and"chaiing ofthe diaphragm andgenerally 'of reducing the =`size, `weightand *costof manufacture of the 'pum-p.

It is broadly to these ends thatthe vinstant `invention 'is directed anditisthought that the designnb'jectives:havebeen achievedwith-`greatersuccess than Ain similar pumpsiheretoforelknown. Toobtainapumpsocharacterized Ais a particular Vobj ect of `th`e`invention.

Another objectof the invention is `to enable `a 're1ati'vely""thindiaphragm to"be used,"with a correspondingincrease in pumping -einciencvIn attaining this object is is'propo'sed to 'providean actuator guidebearing for the diaphragm f-extending axially through "the "pumpingcham-ber andcomprising an actuator working uponflthe diaphragm'from"o'ne "side 'thereof and an Lextension of `said actuatorhaving"a"`bearing in the pump 'Ibo'dyon the opposite side o'fthediaphragm. The Afunction of the extension bearing in inhibiting twisting'and chai-ing` of the diaphragm 4makes possible the use of athindiaphragm Heretofore, the diaphragm has been'made `relatively thickand heavy to`withstandv the veffects of distortion and 'chaiing A'further object of 'the invention is to permit the use of a simplifiedreciprocatingdevice'for the diaphragm, as, "for example, a crank-A and"ec- Acentric mechanical movement, in conjunction with the'describedextension bearing. 1t willbe appreciated that 'the extension `bearingwill-ordinarily require an axial straightline movement of the actuatoron the "opposite side-of `the"`dia phragm. To obtain' such straight linemovement a Vmechanism considerably more elaborate and expensive than a'crank andeccentric device is necessary, however, and the needforsu'chmechanism may negative the advantages gained from use A'of :theextension bearing. By this invention the Abenefits both off-theextension bearing and of the crank-land eccentricactuator-lmaybereallizedinthe sa'rne lp'ump, such oonstructioniloeingmade ipossible, in f-part, aby the :provision fof ra fmovable'imounting@for @theextension bearing per- Amitting andcom-pensatingfortnelslig-htlyarcuate motion in lthe movement of thecraHIcarm.

1Stillfanother-obje`ct l "of `theinventionJ -is to-1ar- 1range the"movablel mounting for thenextension bearing in such manner as ltolrestrict the n`escape of pressure lffluid itliereby from f'the pumpingchamber. l

still further-object ef-ithe inventionis topro- =vide #af *mountingrforithe` Jdiaphragm 1inhibiting Achanr-ig f and lateral-shiftingthereof.

Other objectsfand lstructuraledetails of the invention willappearffromtheifollowingdescrip- `tion `-vvhen-rea'dinf'connectioni-fwith the faccom- -panying drawings, `wherein Fig.` A1is --al Aytop lplanf View; l partly broken away, nf fa diaphragm -`pumpface ordance with the 4invent-ion and n i Fig.i`2 is a view -`in-vertical :longitudinal section, taken-substantially *along the line2-42 of IlFig.` l1-.

Referring -to the drawings-ia 1 diaphragm rl-pump in accordance Mwith-the `=present invention "may comprise* Afirst andi-second -bodyportions Hl and il held in abutting end. to end relation by cennection-screwsiitl `Body member l ll represents the base 1of the! Lpump,lhaving-a Hangei 3 Ato `-ioe bolted to asiiitable support, wwliile bodyymember `H has -thefiormof armate-attached L-to-a'nd mounted onthe'base. rIhe `bod-yor"loaseilllhas a pair lof vertically arrangedlloosses "t4 and f5 spaced Aapartand interconnected lby a `web1f-I'6.The boss vI-"4 presents-anual? terminatingin-an annular space :1*8.s'iniila'rlbore I9 inthe-boss f! 5 Eterminatesina-'similar annularspiace `2 i. The bosses l LIFT #and fl9 function alternatively Aas `theinlet `and ioutletpassages of ithe* pump and are tapered {internal-ly,screw thre'adedat theiroute'r ends for kthe lmaking fof l appropriate lplumbing connections; as; `for example; by a connector 1212, tting 2-3and Avpipe T214" shown I in communication 'with bore fl 1.'Checklvalves-*mounted `infthebores il and i9 determine the function oftheboi-'e'sfas dening #the inlet Eor lou-tiet. yIn reach noire,outwardlyo'fthe spaces -I"8 and 2l isl a` cup -5freceived therein lwitha'pressfit. `"Th tleottomnflthefcup is 'formed "with a plurality'lofiiiid .passing kpenings "-256 and-'isoverla'id by `-a rubberory'rubleie'r-like disc lil *normally fclo'sing the openings. integral;`teat- 2 8 @centrally of" the l disc :is pressed into 'a centralopeningin -thebottom offitlie cup and retainsltheidisc andfeupinioperati-verelation while permitting 'outward fleiiue f'f: fthe fdiscYf-to 3uncover the openings 26. The construction and arrangement of parts issuch that uid pressure entering the open end of the cup 25 is appliedthrough the openings 26 to the disc 21, deforming it to allow free owthrough the openings. Reverse fluid flow is denied by the valve becausethe pressure is exerted in a direction to seat the disc 21 upon thebottom of the cup 25, closing openings 26. The check valves arereversely arranged in the bores I1 and I9 to achieve, in the illustratedinstance, an inward direction of flow in bore I1 and an outwarddirection of ow in bore I9. Accordingly, bore I1 is the inlet passageand bore I6 the outlet passage.

The adjacent faces of the body base I and the body plate II havecomplementary recesses cooperating to define a cylindrical pumpingchamber 29. Openings Bland 32 in the intervening wall between thepumping chamber and the annularspaces I8 and 2l communicate the chamberwith the respective bores I1 and I9. The pumping chamber is verticallypartitioned by a diaphragm 33 peripherally clamped between the abuttingends of members I0 and II in such manner as to provide for limited foreand aft flexure of that portion of the diaphragm within the pumpingchamber. On the periphery of the diaphragm is formed a flange 34 whichis received in aV ring shaped groove 35 in plate member II to inhibitvlateral shifting of the diaphragm.

The diaphragm seals Yol that end f the chamber 29 communicating with theinlet and outlet passages, and in moving through fore and aft motionsalternately increases and decreases the volume of that end of thechamber. In conjunction vvith the check valves in bores I1 and I9,therefore, the diaphragm is eiective when moving in one direction todraw 4fluid into the pumping chamber through opening 3l and when movingin the opposite direction to force the fluid so admitted out of thechamber through opening 32. Resistant effects of vacuum and backpressure upon motion of the diaphragm are avoided by connecting thechamber 29 on the opposite side of the diaphragm to atmosphere through aport 30. Y g

Positive flexure of the diaphragm 33 is accomplished by connectingthereto a crank arm 36 operated by a power driven eccentric 31. 'Iheeccentric 31 is secured to the inner end of a shaft 38 rotatably mountedin a bushing 39 arranged in a .transverse bore in a rearward extensionof plate I I. The outer end of the shaft 38vprojects outside such borefor connection with a source of power, as, for example, through a sheave4I fast on the shaft and driven from an adjoining electric motor (notshown). The eccentric 31 lies in a chamber 42 and is closely sur-mountedby the base end of crank arm 36. Lubrication of the bearing between thecrank arm and eccentric is provided for by a passage 43 which leadsthrough the shaft V38 from an annular lubricant reservoir 44,surrounding the shaft, to the periphery of the eccentric.

In response to rotation of shaft 38, and therefore of eccentric 31, thecrank arm 36 has a reciprocating motion which while primarily axialnecessarily incorporates an arcuate movement due to the action of theeccentric. The outer end of the crank arm -projects into the chamber 29and abuts a rigid disc I5v one of which engages each side of the midportion of the diaphragm. Registering central openings in the discs 45and in the diaphragm permit passage therethrough of a 4 threaded stud 46of reduced diameter integral with and constituting an extension of thecrank arm. A nut 41 on stud 46 is turned up against the disc I5 0n theopposite side of the diaphragm with the result that the diaphragm isclamped to the crank arm and 'partakes of the motion thereof.

A stem 48 is integral with or otherwise secured to the stud 46 andconstitutes a further extension of the crank arm 36. The stem extensionpasses through the chamber 29 and into a bore 49 in the web I6, whichbore is greater in diameter than stem 48 and in the same horizontalplane as the shaft 38. The bore 49 is intersected by a second bore 5I atright angles to the first and in which is mounted a cylindrical bearingmember 52 substantially closing bore 9 and presenting a transverseopening 53 receiving the stem extension 48 with a sliding fit. Themounting for the bearing member 52 is such as to permit free oscillationthereof. IThe bore 5I opens to the exterior of the pump and isordinarily closed by a simple pipe plug 54.

The operation of the pump is largely self evident from the precedingdisclosure. .It will be noted that advantage is taken o a simple crankand eccentric type of mechanical movement to reciprocate the diaphragmand that by the'inn stant invention such movement is utilized inconnection with a bearing for the opposite end of the crank arm asrepresented by the stem extension 48. This is made possible by theconstruction and arrangement of thebylindrical bearing 52, which, beingfree to oscillate, permits and compensates for theV arcuate movementforming a part of the motion of the crank arm. Further', the bearingmember 52 is arranged to inhibit or restrict the flow of pressurethereby from chamber 29.

The provision of such forward bearing for the crank arm serves a usefulpurpose in limiting twisting and chang Vof the diaphragm and so permitsthe use of a relatively thin diaphragm with correspondingly greaterefficiency. As a further guard against such chai-lng, the mating edgesof members I0 andV II in the periphery of theV pumping chamberV 29 aresmoothly curved to avoid sharp edges which might cut into the diaphragm.

The greater eiciency of operation brought about by the structure of theinvention is re- Vilected in a speed of operation and pumping capacitynot ordinarily achieved in pumps of this kind. In a test installation,for example, the pump has been operated for a prolonged period at aspeed of 900 revolutions per minute with a discharge rate ofapproximately 250 gallons per hour. Enabling and facilitating such highspeed operation is the unique check valve construction and the very thindiaphragm. The valves 21 have an exceptionally quick opening' andclosing action, due to inherent resilience and low inertia.The'diaphragm 33, being thin and of light Weight construction is readilyflexed. Moreover', an action resulting from the constructionl andmounting vof the diaphragm has been observed in which an Vannular beadis formed in the diaphragm at the start of its fore and aft strokes,which in straightening provides a forceV for continued momentum of thediaphragm during those short periods of dwell in which the eccentric 31does not exert an axial thrust upon the crank arm 36. As a result ofthis combination of eiects, and'perhaps for other reasons which have notyet been fully determined and analyzed, the

averaged 5, required throw wof the eccentric may be reduced and itsspeed of rotation increased. In the test installation mentioned, the,developed eccentricity is only one-eighth inch for atotal vstroke `ofone quarter inch. With Vfurther regard to the diaphragm, the shortstroke contributes to `a minimizing of abrasive Wear thereon.

What is claimed is: f

l. A diaphragm pump, including a housing presenting inlet and outletports, ai'pumping chamber intercommunicating said inlet and outletports, a flexible diaphragm'insaidchamber, reciprocating means for saiddiaphragm including a crank having a stem portion extending through andbeyond said diaphragm, and a bearing in said housing receiving said stemextension and mounted for rotary motion about an axis substantially atright angles to the axis of said stem extension.

2. A diaphragm pump, including a housing presenting parallel inlet andoutlet ports opening through one end of said housing, oppositelydisposed check valves in said ports, means dening a chamber in theopposite end of said housing, a flexible diaphragm partitioning saidchamber into rst and second compartments, openings connecting said rstcompartment to said inlet and outlet ports, an opening connecting saidsecond compartment to atmosphere, a crank for reciprocating saiddiaphragm having a stem portion extending through said secondcompartment into cooperative relation with said diaphragm and a stemextension projecting from said diaphragm through said rst compartment,and a bearing member mounted for oscillating motion in said housingbetween said inlet and outlet ports receiving said stem extension.

3. A diaphragm pump, including a housing presenting parallel inlet andoutlet passages opening through one end thereof, oppositely disposedcheck valves in said passages, a plate detachably secured to theopposite end of said housing, complementary recesses in said plate andits adjacent end of the housing dening a pumping chamber, communicatingat one side thereof with said inlet and outlet ports and at its otherside with the atmosphere, a flexible diaphragm vertically partitioningsaid pumping chamber and peripherally clamped between said plate andsaid housing, a power driven eccentric rotatably mounted in said plate,a crank arm reciprocable by said eccentric and extending int-o saidpumping chamber into cooperative relation with said diaphragm, anextension on said crank arm projecting beyond said diaphragm, and acylindrical bearing rotatably mounted in said housing between said inletand outlet passages and having a transverse opening receiving saidextension with a sliding fit.

4. A diaphragm pump, including a housing presenting parallel inlet andoutlet passages opening through one end thereof, oppositely disposedcheck valves in said passages, a plate detachably secured to theopposite end of said housing, complementary recesses in said plate andits adjacent end of the housing defining a pumping chamber communicatingon the housing side thereof with said inlet and outlet passages and onthe plate side thereof with the atmosphere, a flexible diaphragmvertically partitioning said chamber and peripherally clamped betweensaid plate and said housing, a power transmission shaft laterallycarried by said plate and formed with an eccentric on its inner end, acrank arm mounted on said eccentric to be reciprocated thereby axiallyyof said diaphragm, said Lrm having a'limited rocking motion by reason offits mounting-on `said eccentric, a stem on said crank arm operativelyengaging said diaphragm `onfthe plate side thereof'and a rigid extensionofsaid stem projecting `beyond said diaphragm into the adjacent end ofSaid housing at a point between said inlet and outlet passages, and acylindrical bearing mounted in said housing at said point for rockingmotion in conjunction with therocking Amotion of said crank armreceiving said extension.

f5. A `diaphragm pump according to Aclaim l4 characterized in that said:cylindrical bearing -is arranged with its axis at 'right angles 'tofsad extension, having a transverse opening -to receive said extension,said bearing being located in intersecting bores in said housing, one ofwhich admits said extension and the other of which provides forinstallation of said bearing.,

6. A diaphragm pump according to claim 5, characterized in that saidcylindrical bearing is arranged substantially to close the former ofsaid bores.

7. A diaphragm pump, including a body presenting inlet and outletpassages arranged in parallel spaced relation and opening through oneend thereof, oppositely disposed check valves in said passages, apumping chamber adjacent the inner ends of said passages, openingsradially oiset with respect to the aXis of said chamber communicatingsaid chamber with said inlet and outlet passages, a diaphragm arrangedfor flexure in said chamber to draw fluid into said chamber through saidinlet passage, and to discharge it through said outlet passage,reciprocable flexing means for said diaphragm including a stem extendingaxially through said chamber and connected to said diaphragm centrallythereof, a bore in said housing to accommodate orne end of said stem, asecond bore transverse to and intersecting the rst, and a cylindricalmember mounted in the second bore and closing' said first bore, saidcylindrical member having a transverse opening to receive said one endof the stem with a sliding fit.

8. A diaphragm pump, including a body presenting a pumping chamber,fluid inlet and outlet passages communicating with one end of saidchamber, a diaphragm arranged for fore and aft flexing movement in saidchamber to effect a ilow of iluid from said inlet passage to said outletpassage through said chamber, a reciprocable crank arm for ilexing saiddiaphragm, said crank arm entering said chamber from the opposite endthereof and comprising an extension portion passing through and beyondsaid diaphragm, a iirst bore in said body opening into said one end ofthe pumping chamber accommodating said extension portion, a second boreat right angles to and intersecting the first, a cylindrical bearingmember mounted in said second bore in position substantially to closesaid iirst bore and presenting a transverse opening receiving saidextension portion with a sliding fit.

9. A diaphragm pump, including rst and second body members arranged inend to end relation with the adjacent faces thereof complementarilyrecessed to define a pumping chamber, valve controlled iluid inlet andoutlet passages in said rst body member opening into one end of saidpumping chamber, a exible diaphragm vertically partitioning said chamberand peripherally clamped between said body members, a ilange on theperiphery of said diaphragm and a oinplemntaryrecess in one of said bodymembers locking said diaphragm against radial shifting motion, areciprocable crank arm mounted in said secondrbody member, and extendinginto said pumping chamber into cooperative relation with Saiddiaphragm,said arm having a stem extension passing centrally through saiddiaphragm, means on said stem extension for clamping said diaphragmagainst axial motion relatively to said `crank arm, and a cylindricalbearing member mounted in said rst body member about an axis at rightangles to said stem extension and having a transverse opening to receivesaid vstem extension with a sliding t, said bearing member being mountedfor oscillation about its axis to permit and compensate for theintroduction of arcuate motion in the movement of said crank arm.

ROBERT VON ROTZ.

imEEmsNoEsl CITE The following references are of Vrecord in the Viile ofthis patent:

UNITED sTATEs PATENTS Number

